Hidden Bosses:
Hidden Bosses can be used once they have been defeated. The conditions of the Bosses to appear are to fulfill two out of the following three conditions. If you play with a Capcom groove you will get Ultimate Rugal, and if you play with a SNK groove you will get Shin Akuma.

Achieve over 1500 GPS by the end of the game.
Defeat the Middle Boss (Geese or Bison/Vega).
Achieve at least one Finest KO.

Custom Grooves:
The Custom Groove option appears once a normal Boss has been defeated (normal Akuma or Rugal). Normal Bosses appear by fulfilling two of the four following conditions.

Achieve over 1000 GPS by the end of the game.
Achieve four or more special KOs.
Middle Boss has appeared.
Achieve two or more LV3 super combo KOs.

One on three tag team mode:
Highlighter any fighter at the character selection screen and press a button. Allow time to run out and the game will start in one on three tag team mode. Note: Do not select one on one battle mode.

Extra options:
Clear Boss challenge mode with no continues. The "Extra Option" becomes available in the game.

Extra color edit mode options:
Press Start while editing the colors for your character to display more options on the left side of the screen.

Middle Boss conditions:
The middle Boss appears when the following conditions are all fulfilled:

No time over has occurred.
The CPU has not made over six "first attacks".
The CPU has not made three or more Special KOs.
Victory quotes:
Hold Start + FP after winning a stage to make your character say an opponent specific quote. Hold Start + FK to make the character talk with a team member.